Automatic hammer



Dec. 17, 1957 R; R. MOlNlCHEN' AUTOMATIC l-LAMMER- Filed April 2, 1956 2 Shams-Shea?l 1 ul' j L 1 I y rraavfyf Dec. 17, 1957 R. R. MolNlcHl-:N g 2,816,289 i AUTOMATIC HAMMER Filed April 2, 1956 2 snets-sneer 2 INVENTOR.

wp/2 BY www United States My invention relates generally to automatic hammers, and more particularly lto such hammers for driving nails having enlarged flat heads such as roofing nails, tacks and the like.

An important object of my invention is the provision of an automatic hammer having novel means for guiding nails in a roW thereof to a receiving position adjacent the striking face of the hammer and for automatically delivering nails singly and in succession from the receiving position to the striking face of the hammer, and for holding the delivered nail against the striking lface during initial driving movement thereof into the Work.

Another object of my invention is the provision of novel work engaging actuator mechanism engageablewith the work to be nailed during striking movement of the hammer for causing the nail delivery mechanism to release the nail being driven and to engage a succeeding nail yfor delivery tothe striking face.

Still another object of my invention is the provision of novel means for holding successive nails at the receiving position, and permitting release thereof when the same is engaged bythe actuator controlled delivery mechanism.

Another object of my invention is the provision of a novel work engaging actuator as set forth which is movable by engagement with the work to be nailed upon operative striking movement of the hammer, to substantial- 1y the vplane of the striking face, whereby the nail may be driven into the Work by a single 'blow of the hammer against'the work.

Another object of my invention is the provision of an automatic hammer as set forth having a head which defines a supplemental striking face by means of which my novel hammer may be used in the conventional manner, the automatic feeding mechanism being unaffected by use of the hammer in 'such vconventional manner.

A still further object of my invention is the provision of an automatic hammer ofthe above type which is relatively simple and inexpensive to manufacture, which is highly efficient in operation, and which is rugged in construction and durable in use.

The above and still 'further highly important objects and advantages of 'my invention will become apparent from the following detailed specification, appended claims and 'attanned drawings.

Referring 'tothe drawings, which illustrate the invention, and in which like characters indicate like 'parts throughout the *several views:

Fig. 1, is a view in side elevation of an automatic hammer built ih accordance with my invention, some parts being broken away and some parts being shown in section; Y

Fig. 2 is an 'enlarged fragmentary view corresponding to a portion of Fig. `1 but showing a different position oi some of the parts;

h Fig. 3`is a fragmentary view inbottom plan as seen from the line 33 of Fig. 1;

Eig. -4 yis an enlarged fragmentary section taken S'ubstam tially on the line 4&4 of Fig. 3;

atent 2,816,289 Patented Dec. 17, 1957 ice Fig. 5 is an enlarged fragmentary view in elevation as seen from the line 5 5 of Fig. 1;

Fig. 6 is a fragmentary detail in section ltaken on the line 6-6 of Fig. 5, some parts being omitted;

Fig. 7l is a fragmentary section taken substantially on the line 7-7 of Fig. 5; v

Fig. 8 is a transverse section taken on the line 8 8 of Fig. l; and

Fig. 9 is a transverse section taken on the line 99 of Fig. y1.

In the preferred embodiment of my invention i1lustrated, an elongated tubular handle as indicated vin its entirety by the numeral 1 having a head 2 rigidly secured to the front end 3 thereof by means of rivets or the like 4. Preferably and as shown, the head 2 extends downwardly from the adjacent end 3 of the handle 1 and defines a striking face `portion 5 and a guide face 6 having lan arcuate guide face portion 7 which extends tangentially rearwardly and upwardly from the striking face portion 5. The guide face 6 extends upwardly within the front end portion 3 ofthe handle 1 and terminates at its upper end .in substantially tangential relationship with the inner top surface 8 of the tubular handle 1, see Figs. l and 2.

Riveted or otherwise rigidly secured within the tubular handle 1 is a pair of guide rails 9 that extend longitudinally of the handle 1 and which dene there-between a passage 10 for reception of the shank portions of nails 11 having diametrically enlarged flat heads 12. As shown in Figs. 1, 2 and 8, the guide rails 9 cooperate with the top inner surface 8 of the handle 1 to denne a passage 13 for the heads 12 of the nails 11. The front end portions of the rails 9, indicated at 14, curve forwardly and downwardly in spaced relation to the guide face *6, and terminate in laterally spaced resilient holding lingers 15 rearwardly adjacent the arcuate guide face portion '7. The forward ends of the lingers 15 are provided with nail engaging stop elements 16, see Figs. 3 and 5, that engage the shanks of the nails 11 immediately below the heads 12 thereof and hold the same against accidental movement toward the striking face 5. inasmuch as a plurality of the nails 11 are carried relatively loosely between the guide rails 9, the same are caused to move forwardly toward the guide face 6 under centrifugal force generated when the hammer is swung in the usual manner, such swinging movement of the hammer being generally about an axis adjacent the rear end 17 of the handle 1. It will be noted that the guide rails 9 are free for lateral movement forwardly of a pair of mounting rivets 18 therefor, toward and away from frictional engagement with opposite sides of the nails 11. A pair of rigid bars 19 are riveted or otherwise rigidly secured to opposite sides of the hammer head 2 below the front end 3 of the handle 1 and extend generally rear- Wardly from opposite sides of the guide face 6 above the arcuate portion 7 thereof. As shown in Fig. 3, a pair of coil compression springs 20 are interposed between the rear end portions of the bars 19 and tbe adjacent guide rail portions 14 and yieldingly urge said guide rail portions 14 and the lfingers 15 toward each other whereby to frictionally hold the rails 11 there-between.

The nails 11 may be fed to the passageways 10 and 13 in the handle 1 by any suitable and well-known means. Such means is shown fragmentarily in Fig. 1 and in Pig. 9 as comprising a tubular conduit 21 having guide means 22 therein, and connecting bars 23 that are adapted to be releasably locked to cooperating bars 24 in the rear end 17 of the handle 1, by suitable means such as large pins or the like 25, one of which is shown in Fig. l. inasmuch as the above-described conduit 21 and means for secur ing the same to the handle 1 do not in themselves comprise'the instant invention, detailed showing an'd'descrip` tion thereof yis deemed unnecessary. Hence, for 'the sake of brevity, such detailed showing and description is omitted.4

lt will be noted with reference to Figs. 1, 2 and 4, that nails 11 at a receiving position between the fingers 15 oi the guide rail portions 14 and against the stop elements 16 are disposed angularly with respect to a nail engaged by the striking face portion S of the hammer head 2, and in rearwardly spaced relation thereto. For the purpose of feeding nails in succession from said receiving position to a driving position, wherein the head 12 of a nail 11 rests against the driving face portion 5. l provide a nail delivering device comprising a pair of arms 26 and 27 that are pivotally secured at their upper and forward ends at opposite sides of the head 2 by a pivot shaft or the like 28 for common swinging movements between a nail engaging position shown in Fig. 2, and a nail delivery and holding position shown in Figs. l, 3, 4, and 7. The arm 26 is provided at its free outer end with an enlarged head 29 having therein a transverse slot 3i? in which is mounted a latch dog 31 dening a cam acting face or edge 32 and a laterally extended nail engaging abutment face 33. The latch dog 31 is further provided with an aperture 34 through which the head portion 29 of the arm 26 extends a pivot pin or the like 35 which journals the latch dog 31 for pivotal movement between an operative nail engaging position indicated by full lines in Fig. 7 and an inoperative position shown by dotted lines therein as will hereinafter be more fully described. A torsion spring in the nature of a resilient finger 36, see Fig. 6, is contained within a longitudinally extending channel 37 in the arrn 26 and has its upper end rigidly secured in the arm 26 as indicated at 38, see Fig. 6. The latch dog 31 is provided with a notch 39 which receives the lower end portion of the spring 36, and by means of which the latch dog 31 is yieldingly urged toward its operative nail engaging position shown by full lines in Fig. 7. It should be noted that, during movement of the arm 26 toward its nail receiving position of Fig. 2, the cam acting surface 32 of the latch dog 31 is engaged by the nail 11 in the receiving position between the lingers is and moved thereby to its inoperative dotted line position of Fig. 7 as the latch dog passes rearwardly and upwardly by said nail 11. When the arm 26 reaches its position of Fig. 2, the latch dog 31 is moved to its operative nail engaging position of Fig. 7 by the spring finger 36, whereupon the abutment face 33 of the latch dog 3l will engage the nail 11 and positively move the same in a direction downwardly and forwardly over the arcuate guide face portion 7 and into engagement of the head 12 thereof with the striking face portion 5 under movement of the arm 26 from its position of Fig. 2 to its position of Fig. 1.

The pivoted arm 27 at its free outer end is provided with a laterally inwardly projecting lug 4l), see Figs. 4 and 7, which provides a seat for a coil compression spring 41 which bears against a nailhead engaging and retaining nger 42 that is pivotally secured to the outer end of the arm 27 by means of a pin or the like 43. The retaining finger 42 is adapted to engage the under-surface of the head 12 of each nail 1l as it is moved from its receiving position between the fingers l5 and hold the nail head 12 against the arcuate guide face portion 7 and the striking face portion 5 until the nail is driven into the work or piece to be nailed, indicated at X in Fig. 2.

The arms 26 and 27 are enlarged at their inner pivoted ends and dene slots 43 in which are pivotally mounted rigid links 44, by means of pivot pins or rivets 45 and on aligned axes. As shown, the rigid links 44 are disposed one each at an opposite side of the hammer head 2 adjacent its lower end, the free ends of said links 44 being pivotally secured to opposite sides of an actuator 46. The actuator 46, at its lower end is provided with a work engaging foot 47 that is movable between a downwardly extended work engaging position in downwardly spaced relation to .the striking face S and a retracted position shown in Fig. 2 at substantially the level of the striking face portion 5. The lower end of the hammer head 2 forwardly of the striking face portion 5 is formed to define a channel 48 for reception of the actuator 46 and a lower end portion 49 that is upwardly spaced from the level of the striking face portion 5 for reception of the work engaging foot 47. The actuator 46 is provided with an upwardly extending shank 50 that is axially movable in an elongated downwardly opening recess 51 for extending and retracting movements with respect to the head 2, and a coil compression spring 52 interposed between the inner end of the recess 51 and the upper end of the shank S0 and yieldingly urges the actuator 46 toward its extended position of Fig. l. With reference to Fig. l, it will be noted that downward movement of the actuator 46 and forward swinging movement of the arms 26 and 27 is limited by engagement of the nail head 12 with the adjacent rear surface of the actuator 46, and the shank of the nail 11 with the abutment surface 33 of the latch dog 31. Obviously, in the absence of a nail 11, the enlarged heads 29 and 40 of the arms 26 and 27 respectively will engage the rear surface of the actuator 46 to thereby limit swinging movement of the arms 26 and 27 and downward movement of the actuator 46. It will further be noted, with reference to Fig. l, that the hammer head 2 is formed to provide an upwardly extending supplemental striking portion which deiines a substantially flat supplemental striking face 54 which enables thev operator to use the hammer in a normal manner.

In use, the magazine defined by the hollow handle 1 and the guide rails 9 is lilled with nails in side by side relationship as shown. The nails 11 move freely between the guideways to the point where the foremost one thereof is lightly frictionally engaged by the fingers 15 adjacent the abutment elements 16 thereof. The actuator 46 is then moved upwardly to its position of Fig. 2 and released to cause a nail 11 to be moved from its receiving position between the lingers 15 to its operative driving position wherein the head 12 thereof lies adjacent the 'actuator 46 and in engagement with the striking face 5. This may be accomplished by manually moving the actuator 46 upwardly and then releasing the same or, the hammer may be struck against an object such as the work X in the manner of driving a nail, the impact between the actuator foot 47 and the work causing the actuator to be retracted to its position of Fig. 2. After such a blow has been struck, the spring 52 will cause the head 2 to be moved with respect to the actuator 46, thereby causing the arms 26 and 27 to be swung to their nail delivering positions of Figs. 1 and 3. With a nail 11 thus being positioned against the striking face portion 5, it is merely necessary for the operator to strike the work X with the hammer, exerting suiicient striking force to cause the nail 11 to be driven home in the work X with a single blow, during which time the arms 26 and 27 are swung to their nail engaging position of Fig. 2. With reference to Fig. 1 it wil1 be seen that the nail 11 projects downwardly from the striking face 5 a distance greater than does the actuator foot 47. With this arrangement, driving of the nail into the work X is initiated just prior to engagement of the foot 47 with the work X. Thus the ynail 11 is assured of being driven true to the work and impact of the actuator foot 47 against the work does not affect the precision with which the nail is driven. With reference to Fig. 3 it will be seen that the space between the adjacent inner surfaces of the enlarged head portions 29 and 40 of the arms 26 and 27 respectively is sufficiently great to permit free movement of the shank of a nail 11 there-between whereas the `distance between the abutment elements 16 is slightly less than the thickness of the nail 11. The compression spring 52 is preferably of such strength that, when the abutment face 33 of the latch dog 31 engages the shank of a nail 11 at the receiving position, the ingers 1S will be spread against bias of the springs 20 suciently to permit passage of the nail 11 between the abutment elements 16. The retaining finger 42 firmly holds the head 12 of the nail 11 against the driving face portion 5 until the nail is started into the work. Then, as soon as the actuator foot 47 engages the work piece, retracting movement of the actuator 46 causes the retaining finger 42 to be moved rearwardly and upwardly with its respective swinging arm 27 toward engagement with a succeeding nail in the receiving position between the fingers 15. In the event that the operator fails to deliver a blow of sufficient strength to cause the nail 11 to be driven completely home in the work X, the operator merely inverts the hammer and utilizes the supplemental driving face 54 to pound the nail completely into the work X, the spring 52 being of sufficient strength to prevent the actuator 46 from partaking of more than a very slight retracting movement due to inertia. Of course, some movement of the actuator 46 is bound to take place during hard striking movement of the hammer in said inverted position, but the spring 52 prevents the actuator from partaking of sufficient retracting movement to cause the nail 11 to be released by the retaining finger 47..

My invention has been thoroughly tested and found to be completely satisfactory for the accomplishment of the objectives set forth; and while I have shown and described a commercial embodiment of my novel automatic hammer, it will be understood that the same is capable of modification, and that modification may be made without departure from the spirit and scope of the invention as defined in the claims.

What I claim is:

l. In an automatic h-ammer, an elongated hollow handle defining a magazine, a downwardly extending head rigidly secured to the front end of said handle and defining a striking face portion at its lower end, means for guiding nails in succession to a receiving position in closely spaced relation to said striking fac-e portion, nail engaging and feeding mechanism mounted on said head for delivering nails singly from said receiving position to an operative driving position and for holding the head of said nail against said striking face portion, an actuator movably mounted on said head, linkage operatively coupling said actuator to said feeding mechanism, said actuator engaging with the work to be nailed upon nail driving movement of the head and moved under the impact thereof against the work and relative to said head in a direction to impart movement to said nail feeding mechanism away from engagement with the delivered nail and into positive feeding engagement with a succeeding nail at said receiving position during movement of said delivered nail into the work, and means for automatically moving said actuator in the opposite `direction upon removal of said striking face portion from the driven nail to cause said feeding mechanism to deliver and hold subsequent nail in driving position against said striking face.

2. In an automatic hammer, an elongated hollow handle defining a magazine, a downwardly extending head rigidly secured to the front end of said handle and dcfining a striking face portion at its lower end and a guide face having an arcuate portion extending tangentially rearwardly and upwardly from said striking face portion, means for guiding nails in succession to a receiving position on said guide face in closely spaced relation to said striking face portion and angularly disposed with respect to said striking face portion, a nail engaging and feeding device mounted on said head for swinging movements about the axis of said arcuate guide face portion for delivering nails singly from said receiving position to an operative driving position and for holding the head of said nail against said striking face portion, and an actuator operatively coupled to said feeding device and engageable with the work to be nailed upon nail driving movement of the head, to be moved under the impact thereof against the work and relative to said head in a direction to impart swinging movement to said device away from engagement with the delivered nail and into positive feeding engagement with a succeeding nail at said receiving position during movement of said delivered nail into the work, and means for automatically moving said actuator in the opposite direction upon removal of said striking face portion from the driven nail to cause said device to deliver andv hold a subsequent nail in driving position against said striking face.

3. The structure defined in claim 2 in which said guide face extends upwardly and rearwardly into said handle, and in which said means for guiding the nails includes a pair of laterally spaced guide rails adapted to receive shank portions of said nails there-between, said guide rails being spaced from said guide face to permit free passage of the heads of said nails between the guide rails and said guide face, said guide rails at their delivery ends having opposed nail engaging stop elements for restraining said nails against feeding movement, the delivery end portions of said rails being laterally outwardly movable to permit movement of said nails beyond said stop elements under feeding movements of said feeding device, and in further combination with yielding means urging said end portions of the guide raiis toward each other to frictionally engage the shank portions of nails therebetween.

4. The structure defined in claim 3 in which said nail engaging and feeding device comprises an arm pivotally secured at one end to one side yof said head, a nail engaging latch dog pivotally mounted on the free end of said arm for swinging movements toward and away from an operative nail engaging position, and yielding means biasing said latch dog toward its operative position, said latch dog having a cam acting surface engaging a nail at said guide face portion during movement of said arm toward said guide face portion and moved by said nail away from its operative position, said latch dog defining a laterally extended abutment surface engaging said nail when the latch dog has passed rearwardly and upwardly there-beyond and upon return movement of said arm toward said striking face portion, to positively move said nail toward said striking face portion.

5. The structure defined in claim 4 in which said nail engaging and feeding device further includes a second arm pivotally secured to the opposite side of said head for common movements with said first-mentioned arm, a nail head engaging finger pivotally secured to the free end of said second arm and engaging the under surface of a nail head, and yielding means biasing said finger toward engagement with said nail head to move the same into engagement with said guide and striking face portions as the nail is carried from its receiving position to said striking face portion.

6. The structure defined in claim 2 in which said actuator includes a stem mounted in said head for extending and retracting movements generally in the direction of movement of said head, a work engaging foot at the lower end of said stern, and a rigid link connected at its opposite ends to said stem and said device.

7. The structure defined in claim 6 in which said means for moving said actuator in the opposite direction comprises a compression spring yieldingly urging said actuator toward its extended work engaging position in downwardly spaced relation to said striking face portion.

References Cited in the file of this patent UNITED STATES PATENTS 1,166,190 Dawson Dec. 28, 1915 1,224,076 Crofoot Apr. 24, 1917 1,550,932 Todd Aug. 25, 1925 

